513498: consume Mylyn Docs from docs release repository

Link Mylyn Docs release artifacts through the composite site rather than
including Docs on the Mylyn site. The enables decoupled release cycles
for Mylyn and Mylyn Docs. 

Change-Id: I0067ac1205d99672303e3023170c5d3360d8b363
Task-Url: https://bugs.eclipse.org/bugs/show_bug.cgi?id=513498
5 files changed